In recent years, in a power source (for example, an engine) used for a vehicle such as an automobile, various electronic controls have been used in order to comply with restrictions regarding fuel savings or emissions control, and the like. In order to perform these electronic controls, a sensor, an actuator, a control device (for example, an electronic control unit: ECU), cables and electrical connectors for connecting equipment, and the like are mainly required.
However, in the vicinity of a power source, in particular, a direct fuel-injection engine or the like, electrical connectors thereof are placed in a harsh environment. That is, because high-acceleration vibration is caused in the vicinity of such a power source, housings of an electrical connector are easily worn away or made defective, which makes it difficult to maintain the durability of the electrical connectors. Further, when high-acceleration vibration of a power source corresponds to a natural frequency of an electrical connector itself, the electrical connector itself falls into a mechanical resonance condition, which makes it further difficult to maintain the durability thereof.
Therefore, when an electrical connector is used in an environment in which high-acceleration vibration is caused, a method has been used in which the electrical connector is led out to a place on which there is less effect of high-acceleration vibration by a leader cable, to be used, and the electrical connector is again returned into an environment in which high-acceleration vibration is caused, with the leader cable.
However, installation of an electrical connector by use of a leader cable results in an increase in the number of components. As a result, spaces are produced among the junctions of the respective components, which cause a reduction in the vibration resistance of the electrical connector.
Further, in a connector which has been disclosed (refer to Patent Document 1), it is necessary to insert a spacer after mating of the connector, a plurality of connecting processes are required for connecting the connector. Therefore, the greater the number of connectors to be installed becomes, the greater the increase in man-hours for connection.
Patent Document 1: Japanese Published Unexamined Patent Application No. 2004-171911.